<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="../react18/react.development.js"></script>
  <script src="../react18/react-dom.development.js"></script>
  <script src="../react18/babel.min.js"></script>
</head>

<body>
  <div id="app"></div>
  <script type="text/babel">

    class App extends React.Component{
      state={
        isHot:true
      }

      render(){
        const {isHot}=this.state
     
    }

    changeWeaHandle=()=>{
      const {isHot}=this.state;
      this.setState({isHot:!isHot})
    }

  }

  const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>)

  </script>
</body>

</html>